Device for securing trim to a seat

ABSTRACT

A seat assembly machine includes a plurality of grippers useful for securing a piece of trim to a seat cushion. In a disclosed example, each gripper includes a plurality of prongs that are moved between neutral, closed and released positions that each facilitate a different portion of the assembly process. In one example, each gripper includes a sleeve within which the prongs are moveable so that the prongs are manipulated between the neutral, closed and released positions. A disclosed example sleeve includes an interior channel having a contour that manipulates the prongs between the different positions based on the location of the prongs within the sleeve.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/471,968 filed Jun. 21, 2006, which claims priority to U.S.Provisional Application No. 60/692,934 filed Jun. 22, 2005.

BACKGROUND OF THE INVENTION

Seat manufacturing techniques are known for making seats such as thoseused in automotive vehicles. Typical seats include a cushion having acontour that establishes a shape of the seat. The cushion is supportedon a seat frame. A covering such as fabric or leather covers over thefoam. The covering is typically referred to as the seat trim. The mannerin which a trim cover conforms to the intended shape of the seat, whichis typically dictated by the shape of the foam cushion and thesupporting seat structure, is commonly referred to as the seatdefinition. The better that the trim conforms to the foam cushion andthe intended seat contour, the better the definition.

There are various known techniques for securing trim onto a seat. Onetechnique includes providing hog rings on the foam and securing the trimto the hog rings using a tying technique. This approach is relativelylabor intensive and time consuming Additionally, there areinconsistencies and inaccuracies with this approach because it is veryoperator dependent. Seat manufacturers require reduced costs and desireuniform quality of seats. The hog ring-tying approach often does notmeet current demands.

Another approach includes gluing trim to the seat foam. While thistechnique is generally reliable for providing good seat definition andmore automated than the hog ring-tying approach, there are drawbacks.The adhesive used during the gluing process typically is heated to cureit for securing the trim to the foam. During the heating and curingprocess, the adhesive hardens. This at least partially reduces thesoftness associated with the foam of the seat cushion. The hardened foamdiminishes seat occupant comfort levels.

Those skilled in the art are always striving to make improvements. Thereis a need for an improved, automated solution for securing trim onto theseat. This invention addresses that need.

SUMMARY OF THE INVENTION

An example seat assembly machine includes a gripper that has a pluralityof prongs retractably moveable relative to a sleeve for gripping a pieceof seat trim. A control is associated with the gripper for manipulatingthe prongs between a neutral position where the prongs are biased towardeach other and allowed to move relative to each other if the bias isovercome, a closed position where the prongs are prevented from movementrelative to each other by the sleeve and a released position where theprongs are separated from each other.

In one example, the sleeve includes a channel within which the prongsmove as they are manipulated between the neutral, closed and releasedpositions. The contour of the channel in one example controls theposition of the prongs based upon the orientation of the prongs relativeto the channel.

One example channel has a varying width along at least a portion of thechannel near one end of the sleeve. The width is wide at the end of thesleeve, narrower at at least one point within the sleeve and then wideagain further inward into the sleeve. The portion of the channel havingthe narrower width is operative to secure the prongs in the closedposition and to move the prongs into the released position as the prongsare manipulated within the sleeve.

An example method of securing trim to a seat cushion includespositioning the seat cushion relative to a plurality of grippers. Eachof the grippers has a plurality of prongs in a neutral position. Anappropriate portion of the trim is received by the prongs while they arein the neutral position. The prongs are then moved into a closedposition where they maintain a firm grip on the trim. The grippers andthe trim are then manipulated relative to the seat foam to secure atleast a portion of the trim into clips that are fixed to the foam. Theprongs of the grippers are then moved into a released position so thatthe trim, which is now connected with the seat foam, can be handled asdesired.

A machine and process designed according to this invention facilitatesautomatically securing seat trim to a seat cushion that results in awell-defined seat appearance and provides consistently reliable results.

The various features and advantages of this invention will becomeapparent to those skilled in the art from the following detaileddescription. The drawings that accompany the detailed description can bebriefly described as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective, diagrammatic illustration of an example machinedesigned according to an embodiment of this invention.

FIG. 2 is a perspective, diagrammatic illustration of an example seatcushion.

FIG. 3 diagrammatically illustrates the example seat cushion of FIG. 2supported on the example machine of FIG. 1.

FIG. 4 schematically illustrates an example piece of seat trim usefulwith the seat cushion of FIG. 2.

FIG. 5 is a partially exploded, partially cross-sectioned view of anexample gripper assembly.

FIGS. 6A and 6B show the example gripper assembly in a neutral position.

FIG. 7 diagrammatically illustrates the example gripper assemblies inthe neutral position of FIGS. 6A and 6B and receiving a portion of theexample trim.

FIG. 8A and 8B show the example gripper assembly in a closed position.

FIG. 9 diagrammatically shows the example grippers in the example closedposition of FIGS. 8A and 8B holding the example piece of trim in aposition during an assembly process.

FIGS. 10A and 10B show the example gripper assembly in a releasedposition that facilitates retrieving the seat cushion and trim after theoperation of the gripper assemblies is complete.

DETAILED DESCRIPTION

This invention provides an automated solution to the process of securingtrim to a seat cushion in an efficient and reliable manner whichprovides improved definition and comfort compared to prior techniques. Adisclosed example arrangement and process facilitates securing trim to aseat cushion as part of an overall seat assembly process.

FIG. 1 diagrammatically illustrates an example machine 20 that is usefulfor securing trim to a seat cushion. The example machine 20 includes aframe 22 and a work surface 24. A plurality of grippers 26 are arrangedon the work surface 24 in a configuration that corresponds to apredetermined pattern based upon a particular seat style, for example. Acontrol 28 is associated with the grippers 26 and allows an operator tocontrol operation of the grippers 26 to facilitate an at least partiallyautomated process for securing trim on a seat cushion.

FIG. 2 diagrammatically shows an example seat cushion 30. This examplemay be used as part of a seat back, for example. A body 32 of theexample seat cushion 30 comprises a known foam material. Trenches 34 areformed in the body 32 in a generally H-shaped pattern. The contours ofthe body 32 and the trenches 34 facilitate establishing the finishedlook or contour of the eventual seat.

In the illustrated example, the trenches 34 include a plurality of clips36. In one example, during the molding process, the clips 36 are held inplace so that they are secured to the foam of the body 32. There areknown techniques for accomplishing this.

The example trenches 34 also include openings 38 which comprisegenerally circular holes extending through the cushion 30. In thisexample, the openings 38 are positioned relative to each othercorresponding to the position of the grippers 26 relative to each othersuch that the cushion 30 can be received onto the work surface 24 asshown in FIG. 3, for example. In this example, one gripper 26 extendsthrough each hole 38. In this position, the grippers 26 are ready forgripping at least a portion of trim that will be applied to the cushion30.

FIG. 4 shows an example piece of trim 40. An underside 42 of the trimpiece 40 is shown in the illustration. An outer side or finished side isfacing downward according to the drawing and is not visible in theillustration. The piece of trim 40 may be fabric or leather, forexample.

One feature of the example piece of trim includes flaps 44 that extendaway from the underside 42. The flaps 44 have a generally H-shapedpattern that corresponds to the arrangement of the trenches 34 on thecushion 30. In one example, an outermost edge of the flaps 44 has aplastic edging that provides an at least somewhat rigid and stablesurface that is received by the clips 36 when the trim piece 40 isapplied to the foam cushion 30. In one example, the plastic edging alsoprovides a surface or feature that the grippers 26 are able to hold ontoduring an assembly process.

The grippers 26 facilitate an assembly process, in part, by manipulatingthe trim flaps 44 relative to the foam cushion 30 and more specificallythe clips 36 for inserting at least a portion of the flaps 44 (e.g., aplastic edging) into the clips 36 to secure the trim piece 40 to thefoam cushion 30. This technique is believed to provide improved seatdefinition without compromising the softness of the foam of the pad 30.In this example, the reception of at least the plastic edging on thetrim flaps 44 within the clips 36 that are fixed in the trenches 34provides good definition and a reliable and secure placement of the trimpiece 40 onto the foam cushion 30.

An example gripper 26 is shown in FIG. 5 partially in cross-section andin a partially exploded view. Each of the grippers of the machine 20 inone example are identical. The example gripper of FIG. 5 includes acylinder 50 and a sleeve 52. In this example, the sleeve 52 istelescopically, at least partially received in the cylinder 50. In oneexample, the cylinder 50 is in a fixed position relative to the worksurface 24. The sleeve 52 can be extended further from or retractedfurther into the cylinder 50 to alter the height of the gripper 26relative to the work surface 24. Movement of the sleeve 52 alsofacilitates an assembly process as will be described. The movement ofthe sleeve 52 in one example is accomplished using a pneumatic actuatorthat is controlled by appropriate manipulation of the control 28 (e.g.,moving a handle or pressing a button).

A plurality of prongs 54 are received at least partially within thesleeve 52. In this example, two prongs 54 are identical to each other.One end 56 of the prongs 54 remains outside of the sleeve 52 throughoutan entire assembly process in one example. Angled or chamfered edges 58are included near the end 56 to facilitate inserting a trim flap 44 orat least plastic edging on such a flap between the prongs 54 such thatthe trim flap is retained between the prongs 54. The illustrated exampleincludes recesses 60 on each of the prongs that provide a grippingsurface for holding onto a corresponding portion of a trim flap receivedbetween the prongs 54.

An opposite end 62 of the prongs 54 remains within the sleeve 52 duringone example assembly process. The ends 62 are biased apart by a biasingmember 64. In this example, the biasing member 64 comprises two coilsprings. A pivot member 66 is positioned between the prongs 54 such thatbiasing apart the ends 62 biases the ends 56 toward each other.

The illustrated example includes a carriage 70 and a rod 72 fixed to thecarriage 70. The prongs 54 and the pivot member 66 are associated withthe carriage 70 such that movement of the rod 72 relative to the sleeve52 causes corresponding movement of the prongs 54 and the carriage 70within the sleeve 52. In this example, a pneumatic actuator controls theposition of the carriage 70 and, therefore, the prongs 54 within thesleeve 52. By manipulating the rod 72 and the carriage 70, the positionof the prongs 54 within the sleeve 52 can be altered to move the prongsbetween a neutral position where the ends 56 are biased toward eachother but able to be separated if the bias is overcome, a closedposition where the ends 56 of the prongs 54 cannot move apart from eachother, and a released position where the ends 56 are separated from eachother.

The example sleeve 52 includes an interior channel 74 that has a contourthat facilitates manipulating the prongs 54 between the neutral, closedand released positions. In this example, the channel 74 has an interiordimension corresponding to a width of the channel, for example. Thechannel 74 is open at an end 76 of the sleeve 52 to facilitate theprongs 54 moving in a retractable manner relative to the sleeve 52 andprotruding out of the sleeve 52 a desired distance, depending on thestage of an assembly process. The example contour includes a taperingportion 80 that provides a wide dimension near the end 76. One end ofthe tapering portion 80 establishes a smaller inside dimension at atransition 82 in the channel 74. Further inward into the sleeve 52another portion 84 has a larger dimension as can be appreciated fromFIG. 5. The position of the prongs 54 relative to the transition 82 andthe tapering portion 80 in this example controls which of the threeoperative positions the prongs are in.

FIGS. 6A and 6B show the example gripper 26 with the prongs 54 in aneutral position. The end 56 of the prongs 54 is spaced from the end 76of the sleeve 52 a first distance. As best appreciated from FIG. 6B, theprongs 54 are within the channel 74 such that there is some clearancebetween outward lateral edges of the prongs 54 and the tapering portion80 of the channel 74. The biasing member 64 biases the ends 62 away fromeach other and biases the ends 56 of the prongs 54 toward each other.Because of the clearance between the prongs 54 and the tapering portion80, the ends 56 of the prongs 54 can be separated if the bias of thebiasing member 64 is overcome. This can be accomplished, for example, byan operator using his finger to pry apart the ends 56 of the prongs 54.This can also be accomplished by inserting an edge of the trim flap 44between the prongs 54. The illustrated example includes the ramped orchamfered surface 58 to facilitate inserting at least an edge of thetrim flap 44 between the prongs 54, even in the presence of the bias ofthe biasing member 64. Keeping the ends 56 biased toward each otherfacilitates more easily placing the trim flap 44 within the grip of thegrippers 26.

FIG. 7 diagrammatically illustrates a plurality of the grippers 26holding a received edge of a trim flap 44 while the grippers 26 are inthe neutral position shown in FIGS. 6A and 6B. This is accomplished inone example by an operator manually inserting at least the edge of thetrim flap 44 between the prongs 54 of each gripper 26. Once this isaccomplished for all grippers and all trim flaps of a particular seatarrangement, the machine 20 can be used for securing the trim flaps 44to the clips 36 on the seat cushion 30.

To facilitate this, the grippers 26 are controlled so that the prongs 54move into a closed position where the ends 56 are secured against movingapart, which securely retains the trim flap 44 in the grippers 26. FIGS.8A and 8B show a gripper 26 with the prongs 54 in the closed position.In this position, the end 56 of each prong 54 is spaced from the end 76of the sleeve 52 a second distance that is smaller than the firstdistance associated with the neutral position shown in FIG. 6A, forexample.

As can be appreciated from FIG. 8B, the pivot member 66 is retractedfurther into the sleeve than the transition 82 of the channel 74. Inthis position, the prongs 54 cannot move away from each other so thatthe ends 56 are secured in the closed position, which prevents the trimflap 44 from being inadvertently removed from a gripper during anassembly process. In the position of FIG. 8B, the outward lateral edgesof the prongs 54 are received directly against the channel 74 at thetransition 82. This prevents outward movement of the ends 56 relative toeach other. The prongs 54 are moved into this example position byappropriate movement of the carriage 70 and the rod 72 (which are notshown in FIG. 8B for clarity but are shown in FIG. 5).

Once the prongs 54 are in the closed position, the sleeve 52 can beretracted relative to the cylinder 50 so that the edge of the trim flap44 is brought closer to and eventually inserted at least partially intothe clips 36. This movement of the sleeve 52 relative to the cylinder 50in the illustrated example corresponds to the sleeve 52 moving downwardand inward further into the cylinder 50. This movement corresponds tomoving the sleeve 52 from the position shown in FIG. 7 to the positionshown in FIG. 9, for example. As can be appreciated from FIG. 9, an edgeon the trim flap 44 has now been secured within the clips 36 as a resultof the movement of the grippers 26. At this point, the grippers 26 canbe released and the cushion 30 and trim 40 can be retrieved (e.g.,removed from the work surface 24) for further manipulation of the trim40 onto the cushion 30 and completion of a seat assembly process. Theillustrated example grippers 26 facilitate the retrieval of the trim 40and cushion 30 by an automatic manipulation of the prongs 54 into areleased position.

FIGS. 10A and 10B show the example prongs 54 in a released position. Inthis position, the ends 56 of the prongs 54 are spaced from the end 76of the sleeve 52 a third distance that is greater than the firstdistance associated with the neutral position (shown in FIG. 6A forexample). In the released position, the ends 56 of the prongs 54 areseparated from each other.

As can be appreciated from FIG. 10B, by moving the rod 72, carriage 70and prongs 54 further outward in the channel 74, the ends 62 eventuallyapproach the transition 82. The reduced interior dimension of thechannel 74 at the transition 82 effectively pushes the ends 62 towardeach other against the bias of the biasing member 64. At the same time,because of the presence of the pivot member 66, the ends 56 areseparated from each other. The contour and dimension of the taperedportion 80 controls the amount of separation of the ends 56 of theprongs 54.

After the assembled cushion and trim piece 40 are removed from the worksurface 24, the rod 72 and carriage 70 are drawn inward within thesleeve 52 to return the prongs 54 to the neutral position. The sleeve 52also moves outward from the cylinder 50 to return to the position shownin FIG. 1, for example, for receiving another cushion and trim foranother seat.

The automated movement of the prongs between the neutral position, theclosed position and the released position facilitates an assemblyprocess where the trim 40 can be secured to the cushion 30 using a trimflap and clip arrangement as included in the illustrated example. Havingthe prongs in a neutral position allows for readily placing the trimwithin the grip of the grippers 26. Subsequently moving the prongs 54into the closed position secures the trim in the grip of the grippers tofacilitate a reliable manipulation of the trim so that the trim flap isappropriately received and grasped by the clips 36. Automatically movingthe prongs into the released position facilitates proceeding to asubsequent step of seat assembly. Accordingly, the disclosed examplefacilitates an automated process of securing the piece of trim 40 to theseat cushion 30.

The preceding description is exemplary rather than limiting in nature.Variations and modifications to the disclosed examples may becomeapparent to those skilled in the art that do not necessarily depart fromthe essence of this invention. The scope of legal protection given tothis invention can only be determined by studying the following claims.

1. A seat assembly machine comprising: a gripper that has two prongsretractably retained within a sleeve for gripping a piece of seat trim;and a control associated with the gripper for manipulating a position ofthe prongs between a closed position where the prongs are prevented frommovement relative to each other by the sleeve, a released position wherethe prongs are separated from each other, and a neutral position wherethe prongs are biased toward each other and allowed to move relative toeach other if the bias is overcome.
 2. The seat assembly machine ofclaim 1, comprising a plurality of grippers.
 3. The seat assemblymachine of claim 2, wherein the plurality of grippers are arranged tomaintain a seat cushion in a desired position when the plurality ofgrippers are at least partially received in a corresponding plurality ofholes in the seat cushion.
 4. The seat assembly machine of claim 1,comprising at least one spring that biases at least one end of theprongs toward one another when the prongs are in the neutral position.5. The seat assembly machine of claim 1, wherein the sleeve comprises achannel having a contour that controls whether the prongs are in theneutral, closed or released position based on a location of the prongsrelative to the sleeve.
 6. The seat assembly machine of claim 1, whereinone end of the prongs is a first distance from an end of the sleeve whenthe prongs are in the neutral position; the one end of the prongs is asecond, smaller distance from the end of the sleeve when the prongs arein the closed position; and the one end of the prongs is a thirddistance from the end of the sleeve when the prongs are in the releasedposition, the third distance is greater than the first distance.
 7. Theseat assembly machine of claim 1, wherein the prongs are resilientlybiased toward one another.
 8. The seat assembly machine of claim 1,wherein at least one prong includes a chamfered surface facing anotherprong to allow insertion of an edge of trim.
 9. The seat assemblymachine of claim 8, wherein the chamfered surface allows insertion ofthe edge of trim when the prongs are in the neutral position.
 10. A seatassembly machine comprising: a gripper that has two prongs retractablyretained within a sleeve for gripping a piece of seat trim; a controlassociated with the gripper for manipulating a position of the prongsbetween a closed position where the prongs are prevented from movementrelative to each other by the sleeve, a released position where theprongs are separated from each other, and a neutral position where theprongs are biased toward each other and allowed to move relative to eachother if the bias is overcome; and at least one spring that biases atleast one end of the prongs toward one another when the prongs are inthe neutral position.
 11. A seat assembly machine comprising: a gripperthat has two prongs retractably retained within a sleeve for gripping apiece of seat trim; and a control associated with the gripper formanipulating a position of the prongs between a closed position wherethe prongs are prevented from movement relative to each other by thesleeve, a released position where the prongs are separated from eachother, and a neutral position where the prongs are biased toward eachother and allowed to move relative to each other if the bias isovercome, wherein the sleeve comprises a channel having a contour thatcontrols whether the prongs are in the neutral, closed or releasedposition based on a location of the prongs relative to the sleevewherein the contour comprises a tapering portion near an open end of thesleeve having a first interior dimension near the open end; a transitionnear an end of the tapering portion within the sleeve having a second,smaller interior dimension; and another portion further inward into thesleeve having a third interior dimension that is larger than the secondinterior dimension.
 12. The seat assembly machine of claim 11, whereinthe transition abuts lateral edges of the prongs to prevent relativemovement between the prongs when the prongs are in the closed position.13. The seat assembly machine of claim 11, wherein the tapering portioncontrols a distance between the prongs when the prongs are in thereleased position.
 14. The seat assembly machine of claim 1, whereineach of the closed position, released position, and neutral positioncorresponds to a different axial position of the prongs relative to thesleeve.